Method and electronic device for providing authentication using an image sensor

ABSTRACT

Accordingly, the embodiments herein provide a method for providing authentication using at least one image sensor of an electronic device. The method includes receiving, by the electronic device, a plurality of frames from the at least one image sensor of the electronic device, where each frame includes a plurality of Optical Black (OB) pixels. Further, the method includes determining, by the electronic device, at least one set of optimal OB pixels from the plurality of frames. Further, the method includes generating, by the electronic device, at least one unique key based on the at least one set of optimal OB pixels for the authentication.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119 to Indian Provisional Patent Application No. 201941048293, filed on Nov. 26, 2019 and Indian Non-Provisional Patent Application No. 201941048293 filed on Nov. 23, 2020 in the Indian Patent Office, the disclosures of which are incorporated by reference herein in their entireties.

TECHNICAL FIELD

The present invention relates to image processing, and more specifically related to a method and electronic device for providing authentication using an image sensor.

BACKGROUND

In existing systems, an unique identification (ID) such as an international mobile equipment identity (IMEI) or an international mobile subscriber identity (IMSI) assigned to an electronic device can be easily duplicated or changed. The unique ID is obtained from an operating system (OS), and can be easily cloned, forged, or misused to tap or hack the electronic device. Further, a media access control (MAC) address assigned when the electronic device is connected to a network is intended to be set and fixed uniquely and permanently worldwide so that the MAC address can be used as the unique ID of the electronic device. However, existing systems are capable to do MAC spoofing by modifying the MAC address of the electronic device. So, the existing systems fail because of a drawback of having difficulty in guaranteeing the uniqueness of the identity of the electronic device.

Thus, it is desired to address the above-mentioned disadvantages or other shortcomings or at least provide a useful alternative.

SUMMARY

The principal object of the embodiments herein is to generate a physically unclonable function (PUF) (i.e. an unique key) based on optical black (OB) pixel of a complementary metal oxide semiconductor (CMOS) image sensor of an electronic device for authentication without using an external hardware.

Accordingly, the embodiments herein provide a method for providing authentication using an image sensor of an electronic device. The method includes receiving, by the electronic device, a plurality of frames from the image sensor of the electronic device, where each frame includes a plurality of OB pixels (reference pixels within the image sensor's pixel array that have virtually identical electrical characteristics as a standard active pixel, yet are insensitive to light). Further, the method includes determining, by the electronic device, set of optimal OB pixels from the plurality of frames. Further, the method includes generating, by the electronic device, a unique key based on the set of optimal OB pixels for the authentication.

In an embodiment, further the method includes determining, by the electronic device, location information of a plurality of candidate OB pixels (candidate OB pixels are pixels whose values are above a threshold range, the threshold is tunable parameter which varies with the image sensor) in a first frame of the plurality of frames, where the plurality of candidate OB pixels obtained from the plurality of OB pixels. Further, the method includes storing, by the electronic device, the location information of the plurality of candidate OB pixels. Further, the method includes determining, by the electronic device, location information of a plurality of candidate OB pixels in remaining frames of the plurality of frames. Further, the method includes performing, by the electronic device, an intersection on the stored location information using the location information of the plurality of candidate OB pixels of the remaining frames. Further, the method includes determining, by the electronic device, the set of optimal OB pixel based on the intersection.

In an embodiment, further the method includes determining, by the electronic device, location information of a plurality of OB pixels in the first frame of the plurality of frames. Further, the method includes storing, by the electronic device, the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels, the dark current that is proportional to temperature. Because of structural/process variation among the OB Pixels, dark current change in magnitude based on the location information. Further, the method includes determining, by the electronic device, location information of a plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in the remaining frames of the plurality of frames. Further, the method includes performing, by the electronic device, an addition between the stored dark current value of the plurality of OB pixels and the determined dark current value of the plurality of OB pixels of the remaining frames and storing an average information of the addition. Further, the method includes determining, by the electronic device, the set of optimal OB pixel based on the average information, where the set of optimal OB pixel is a higher value set of the stored addition information.

In an embodiment, further the method includes determining, by the electronic device, the location information of the plurality of OB pixels in the first frame of the plurality of frames. Further, the method includes storing, by the electronic device, the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels, where the stored location information is a higher value set of the first frame. Further, the method includes determining, by the electronic device, the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in the remaining frames of the plurality of frames. Further, the method includes performing, by the electronic device, the addition between the stored dark current value of the plurality of OB pixels and the determined dark current value of the plurality of OB pixels of the remaining frames and storing the addition information. Further, the method includes determining, by the electronic device, the set of optimal OB pixels based on the addition, where a set of optimal OB pixels is the higher value set of the stored addition information.

In an embodiment, the plurality of OB pixels are present on an active pixel array of the image sensor of the electronic device. In an embodiment, further the method includes generating, by the electronic device, a plurality of parity bits from the generated a unique key. Further, the method includes detecting an error based on the generated plurality of parity bits.

Accordingly, the embodiments herein provide the electronic device for providing the authentication using the image sensor of the electronic device. The electronic device includes a processor and a memory and an authentication engine, where the authentication engine is coupled with the processor and the memory. The authentication engine is configured to receive the plurality of frames from the image sensor of the electronic device, where each frame includes the plurality of OB pixels. Further, the authentication engine is configured to determine the set of optimal OB pixels from the plurality of frames. Further, the authentication engine is configured to generate the unique key based on the set of optimal OB pixel for the authentication.

These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF DRAWINGS

This method and electronic device are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:

FIG. 1 illustrates a block diagram of an electronic device for providing an authentication using an image sensor of the electronic device, according to the embodiments as disclosed herein;

FIG. 2 is a flow diagram illustrating various operations for determining set of optimal OB pixel based on an intersection of multiple frames to provide the authentication using the image sensor of the electronic device, according to the embodiments as disclosed herein;

FIG. 3 is a flow diagram illustrating various operations for determining the set of optimal OB pixel based on an average information of the multiple frames to provide the authentication using the image sensor of the electronic device, according to the embodiments as disclosed herein;

FIG. 4 is a flow diagram illustrating various operations for determining the set of optimal OB pixel based on the addition information of the multiple frames for approximate processing to provide the authentication using the image sensor of the electronic device, according to the embodiments as disclosed herein; and

FIG. 5 is an example flow diagram illustrating various operations for generating a parity bit for the multiple frames at various temperatures, according to the embodiments as disclosed herein.

DETAILED DESCRIPTION OF FIGURES

The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. Also, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments. The term “or” as used herein, refers to a non-exclusive or, unless otherwise indicated. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein can be practiced and to further enable those skilled in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

As is traditional in the field, embodiments may be described and illustrated in terms of blocks which carry out a described function or functions. These blocks, which may be referred to herein as managers, units, modules, hardwire components or the like, are physically implemented by analog and/or digital circuits such as logic gates, integrated circuits, microprocessors, microcontrollers, memory circuits, passive electronic components, active electronic components, optical components, hardwired circuits and the like, and may optionally be driven by firmware. The circuits may, for example, be embodied in one or more semiconductor chips, or on substrate supports such as printed circuit boards and the like. The circuits constituting a block may be implemented by dedicated hardware, or by a processor (e.g., one or more programmed microprocessors and associated circuitry), or by a combination of dedicated hardware to perform some functions of the block and a processor to perform other functions of the block. Each block of the embodiments may be physically separated into two or more interacting and discrete blocks without departing from the scope of the disclosure. Likewise, the blocks of the embodiments may be physically combined into more complex blocks without departing from the scope of the disclosure.

Accordingly, the embodiments herein provide a method for providing authentication using an image sensor of an electronic device. The method includes receiving, by the electronic device, a plurality of frames from the image sensor of the electronic device, where each frame includes a plurality of OB pixels. Further, the method includes determining, by the electronic device, set of optimal OB pixels from the plurality of frames. Further, the method includes generating, by the electronic device, a unique key based on the set of optimal OB pixels for the authentication. Further, each pixel in the image sensor (e.g. CMOS sensor) is made up of transistors and each transistor has unique physical variations that occur naturally during a semiconductor manufacturing process. The unique physical variations are unpredictable and uncontrollable, which makes the unique physical variations impossible to clone the unique key (i.e. PUF key).

Accordingly, the embodiments herein provide the electronic device for providing the authentication using the image sensor of the electronic device. The electronic device includes a processor and a memory and an authentication engine, where the authentication engine is coupled with the processor and the memory. The authentication engine is configured to receive the plurality of frames from the image sensor of the electronic device, where each frame includes the plurality of OB pixels. Further, the authentication engine is configured to determine the set of optimal OB pixels from the plurality of frames. Further, the authentication engine is configured to generate the unique key based on the set of optimal OB pixel for the authentication.

Referring now to the drawings, and more particularly to FIGS. 1 through 5, where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred embodiments.

FIG. 1 illustrates a block diagram of an electronic device (100) for providing authentication using an image sensor (150) the electronic device (100), according to the embodiments as disclosed herein. The electronic device (100) can be, for example, but not limited, to a smart phone, a laptop, a smart television (TV), smart phone cameras, web cameras, modem digital pocket cameras, digital single-lens reflex cameras (DSLRs), and mirror less interchangeable-lens cameras (MILCs). In an embodiment, the electronic device (100) includes a memory (110), a processor (120), a communicator (130), a display (140), an image sensor (150) and an authentication engine (160).

The memory (110) stores instructions to be executed by the processor (120). The memory (110) may include non-volatile storage elements. Examples of such non-volatile storage elements may include magnetic hard discs, optical discs, floppy discs, flash memories, or forms of electrically programmable memories (EPROM) or electrically erasable and programmable (EEPROM) memories. In addition, the memory (110) may, in some examples, be considered a non-transitory storage medium. The term “non-transitory” may indicate that the storage medium is not embodied in a carrier wave or a propagated signal. However, the term “non-transitory” should not be interpreted that the memory (110) is non-movable. In some examples, the memory (110) can be configured to store larger amounts of information than a data storage space of the memory (110). In certain examples, a non-transitory storage medium may store data that can, over time, change (e.g., in random access memory (RAM) or cache). In an embodiment, the memory (110) can be an internal storage unit or an external storage unit of the electronic device (100), a cloud storage, or any other type of external storage.

The processor (120) communicates with the memory (110), the communicator (130), the display (140), the image sensor (150), and the authentication engine (160). The processor (120) is configured to execute instructions stored in the memory (110) and to perform various processes. The processor may include one or a plurality of processors, may be a general purpose processor, such as a central processing unit (CPU), an application processor (AP), or the like, a graphics-only processing unit such as a graphics processing unit (GPU), a visual processing unit (VPU), and/or an Artificial intelligence (AI) dedicated processor such as a neural processing unit (NPU). The communicator (130) is configured to communicate internally between internal hardware components (i.e. the memory (110), the processor (120), the display (140), the image sensor (150) and the authentication engine (160)) of the electronic device (100). The communicator (130) is configured to communicate the electronic device (100) with external devices via one or more networks.

In an embodiment, the authentication engine (160) includes a frame controller (161), a dark pixel marker (162), an image processing controller (163), a key generator (164), and an error detector (165). The authentication engine (160) is implemented by processing circuitry such as logic gates, integrated circuits, microprocessors, microcontrollers, memory circuits, passive electronic components, active electronic components, optical components, hardwired circuits, or the like, and may optionally be driven by firmware. The circuits may, for example, be embodied in one or more semiconductor chips, or on substrate supports such as printed circuit boards and the like. The frame controller (161) receives a plurality of frames from the image sensor (150) of the electronic device (100). The frame includes a plurality of OB pixels present on an active pixel sensor (APS) (i.e. image sensor (150)). Different types of APS include an early N-type metal-oxide-semiconductor (NMOS) APS, a CMOS APS, etc. The CMOS APS is also known as the CMOS sensor, which is widely used in digital camera technologies such as smart phone cameras, web cameras, modern digital pocket cameras, DSLRs, and MILCs. Further, the frame controller (161) passes one frame at a lime from the plurality of the frames to the image processing controller (163).

The dark pixel marker (162) determines location information of a plurality of candidate OB pixels and a plurality of OB pixels in the received frames from the image sensor (150) of the electronic device (100). Further, the dark pixel marker (162) stores the location information of the plurality of candidate OB pixels, the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels store in the memory (110).

The image processing controller (163) performs an intersection on the stored location information of the plurality of candidate OB pixels of a first frame of the plurality of frames using the location information of the plurality of candidate OB pixels of remaining frames of the plurality of frames. Further, the image processing controller (163) determines set of optimal OB pixel based on the intersection. For example, let there be a set “S1” of candidate pixel location from the first frame “F1”, S1={a1, a2, b1, b2, b3}. Let there be a set “S2” of candidate pixel location front a second frame “F2”, S2={a1, b1, b3, b4}. Let R be the set of optimal OB pixel after the intersection of the S1 & S2, then R should be {a1, b1, b3}. This will likewise be extended to the remaining frames.

Further, the image processing controller (163) performs an addition between the stored dark current value of the plurality of OB pixels of the plurality of OB pixels of the first frame of the plurality of frames and the determined dark current value of the plurality of OB pixels of the remaining frames of the plurality of frames and stores an average information of the addition in the memory (110). Further, the image processing controller (163) determines the set of optimal OB pixels based on the addition, the set of optimal OB pixels is a higher value set of the stored average information. For example, let there be the first frame “F1” and the buffer “S1” (i.e. the memory (110)) which stores the OB pixel value (i.e. dark current value) & OB pixel location of the first frame “F1”. Now for the second frame “F2”, the OB pixel value of the frame “F2” added to the buffer “S1” at their respective locations, and average is calculated. From the calculated average of top “K pixel” forms the set of optimal OB pixels. This will likewise be extended to the remaining frames.

Further, the image processing controller (163) performs the addition between the stored dark current value of the plurality of OB pixels (i.e. higher value set of the first frame) and the determined dark current value of the plurality of OB pixels of the remaining frames and storing addition information in the memory (110). Further, the image processing controller (163) determines the set of optimal OB pixels based on the addition, where the set of optimal OB pixel is a higher value set of the stored addition information. For example, let there be the first frame “F1” and the buffer “F1” which stores the OB pixel value & OB pixel location of the first frame “F1” for only top “L pixel location” of the first frame “F1” (not processing entire OB region of the first frame “F1”) Now for the second frame “F2”, the OB pixel value & OB pixel location determines from the same top “L pixel location” as stored during the first frame “F1” and then calculate average. This will likewise be extended to the remaining frames. Instead of running on the whole OB region, the advantage of the method is that it is only performed on a limited collection of OB pixels, effective in terms of memory and can be applied in the real time system.

The key generator (164) generates the unique key based on the set of optimal OB pixel for the authentication. Once the optimal pixel set is generated from the image processing engine (163). The key generator (164) generates a binary key where 0 represent pixel is not optimal pixel and 1 represent pixel is optimal pixel. E.g. consider there are 10 pixels. Now optimal OB pixel set from the Image processing engine (163) be (1, 5, 9). The unique key for this scenario will be 0100010001. The error detector (165) detects an error related to a pixel value fluctuation due to a temperature variation. For example, consider “W” as row width for the image sensor (150), and “L” rows of the OB pixels. So, there are M=L*W the OB pixels per frame and signature or key for sensor k is defined as per equation 1,

X ^(k) =[x ₀ , x ₂ . . . , x _(M−1) ], x _(i)∈{0,1}  (1)

A value of pixels might change based on the temperature variation. Hence, a helper data (or parity data) is needed to restore the value of the pixel. Consider, that t bits of error correction are added, then m*t bits of parity are added, m is size of Finite Field (Galois Field) over which error correction code is defined. So that M+m*t<2^(m) bose-chaudhuri-hocquenghem (BCH) codes. The m*t bits of data are stored in an one-time-programmable (OTP) in the memory (110) at time 0, where the data is called as the helper data. The error detector (165) uses extra bits to detect the error beyond t bits for an extra protection. The error correction (parity Generation BCH) provides reliability against the image sensor (150) aging along with temperature.

Although the FIG. 1 shows various hardware components of the electronic device (100) but it is to be understood that other embodiments are not limited thereon. In other embodiments, the electronic device (100) may include less or more number of components. Further, the labels or names of the components are used only for illustrative purpose and does not limit the scope of the invention. One or more components can be combined together to perform same or substantially similar function to provide authentication using the image sensor (150) of the electronic device (100).

FIG. 2 is a flow diagram (S200) illustrating various operations for determining the set of optimal OB pixel based on the intersection of the multiple frames to provide the authentication using the image sensor (150) of the electronic device (100), according to the embodiments as disclosed herein. The operations (S202-S218) are performed by the authentication engine (160).

At S202, the method includes receiving the first frame of the plurality of frames (e.g. ten frames) from the image sensor (150) of the electronic device (100), where each frame includes the plurality of OB pixels. At initial stage (i.e. when the first frame is received), a counter value is set to zero. At S204, the method includes determining whether a counter value during reception of the first frame is lower than a threshold value (i.e. N). At S206, the method includes determining the location information of the plurality of candidate OB pixels in the received frame (i.e. the first frame) in response to determining that the counter value during reception of the first frame is lower than the threshold value.

At S208, the method includes determining whether the received frame is the first frame of the plurality of the frames. At S210, the method includes storing the location information of the plurality of candidate OB pixels in the memory (110) in response to determining that the received frame is the first frame of the plurality of the frames. At S212, the method includes increasing the count value by one.

Now, second cycle for remaining frames (e.g. second frame, third frame, etc.), at S204, the method includes determining whether the counter value during reception of the remaining frames is lower than the threshold value. At S206, the method includes determining the location information of the plurality of candidate OB pixels in the remaining frames in response to determining that the counter value during reception of the remaining frames is lower than the threshold value. At S208, the method includes determining whether the remaining frames is the first frame of the plurality of the frames. At S214, the method includes performing the intersection on the stored location information using the location information of the plurality of candidate OB pixels of the remaining frames in response to determining that the received frame is not the first frame of the plurality of the frames. At S212, the method includes increasing the counter value by one. The second cycle, performs repeatedly till the counter value is lower than the threshold value. At S216, the method includes determining the set of optimal OB pixels from the plurality of frames based on the intersection in response to determining that the counter value is higher than the threshold value. At S218, the method includes generating the unique key based on the set of optimal OB pixel for the authentication.

FIG. 3 is a flow diagram (S300) illustrating various operations for determining the set of optimal OB pixel based on the average information of the multiple frames to provide the authentication using the image sensor (150) of the electronic device (100), according to the embodiments as disclosed herein. The operations (S302-S318) are performed by the authentication engine (160).

At S302, the method includes receiving the first frame of the plurality of frames (e.g. ten frames) from the image sensor (150) of the electronic device (100), where each frame includes the plurality of OB pixels. At initial stage (i.e. when the first frame is received), a counter value is set to zero. At S304, the method includes determining whether a counter value during reception of the first frame is lower than a threshold value (i.e. N). At S306, the method includes determining the location information of the plurality of OB pixels in the received frame (i.e. the first frame) and corresponding dark current value of the plurality of OB pixels in response to determining that the counter value during reception of the first frame is lower than the threshold value.

At S308, the method includes determining whether the received frame is the first frame of the plurality of the frames. At S310, the method includes storing the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in the memory (110) in response to determining that the received frame is the first frame of the plurality of the frames. At S212, the method includes increasing the count value by one.

Now, second cycle for remaining frames (e.g. second frame, third frame, etc.), at S304, the method includes determining whether the counter value during reception of the remaining frames is lower than the threshold value. At S306, the method includes determining the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in the remaining frames in response to determining that the counter value during reception of the remaining frames is lower than the threshold value. At S308, the method includes determining whether the remaining frames is the first frame of the plurality of the frames. At S314, the method includes performing the addition between the stored dark current value of the plurality of OB pixels and the determined dark current value of the plurality of OB pixels of the remaining frames and storing the average information of the addition in response to determining that the received frame is not the first frame of the plurality of the frames. At S312, the method includes increasing the counter value by one. The second cycle, performs repeatedly till the counter value is lower than the threshold value. At S316, the method includes determining the set of optimal OB pixels from the plurality of frames based on the average information in response to determining that the counter value is higher than the threshold value, the set of optimal OB pixel is a higher value set of the stored average information. At S318, the method includes generating the unique key based on the set of optimal OB pixel for the authentication.

FIG. 4 is a flow diagram (S400) illustrating various operations for determining the set of optimal OB pixel based on the addition information of the multiple frames for approximate processing to provide the authentication using he image sensor (150) of the electronic device (100), according to the embodiments as disclosed herein. The operations (S402-S418) are performed by the authentication engine (160).

At S402, the method includes receiving the first frame of the plurality of frames (e.g. ten frames) from the image sensor (150) of the electronic device (100), where each frame includes the plurality of OB pixels. At initial stage (i.e. when the first frame is received), a counter value is set to zero. At S404, the method includes determining whether a counter value during reception of the first frame is lower than a threshold value (i.e. N). At S106, the method includes determining the location information of the plurality of OB pixels in the received frame (i.e. the first frame) and corresponding dark current value of the plurality of OB pixels in response to determining that the counter value during reception of the first frame is lower than the threshold value.

At S408, the method includes determining whether the received frame is the first frame of the plurality of the frames. At S410, the method includes storing the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in the memory (110), the stored location information is the higher value set of the first frame in response to determining that the received frame is the first frame of the plurality of the frames. At S412, the method includes increasing the count value by one.

Now, second cycle for remaining frames (e.g. second frame, third frame, etc.), at S404, the method includes determining whether the counter value during reception of the remaining frames is lower than the threshold value. At S406, the method includes determining the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in the remaining frames in response to determining that the counter value during reception of the remaining frames is lower than the threshold value. At S408, the method includes determining whether the remaining frames is the first frame of the plurality of the frames. At S414, the method includes performing the addition between the stored dark current value of the plurality of OB pixels and the determined dark current value of the plurality of OB pixels of the remaining frames and storing the addition information in response to determining that the received frame is not the first frame of the plurality of the frames. At S412, the method includes increasing the counter value by one. The second cycle, performs repeatedly till the counter value is lower than the threshold value. At S416, the method includes determining the set of optimal OB pixels from the plurality of frames based on the addition information in response to determining that the counter value is higher than the threshold value, the set of optimal OB pixel is a higher value set of the stored addition information. At S418, the method includes generating the unique key based on the set of optimal OB pixel for the authentication.

FIG. 5 is an example flow diagram illustrating various operations for parity bit generation For multiple frames at various temperatures, according to the embodiments as disclosed herein. At 502-506, the authentication engine (160) receives the plurality of frames from the image sensor (150) at various temperatures (e.g. T1=27° c., T2=−5° c., T3=65° c.). At 508, the authentication engine (160) determines the set of optimal OB pixel from the plurality of frames. At 510-514, the authentication engine (160) generates the unique key based on the set of optimal OB pixel for the authentication at various temperatures. At 516, the authentication engine (160) counts the bit flips for each unique key based on the set of optimal OB pixel for the authentication at various temperatures. At 518-520, the authentication engine (160) calculates BCH code (M+m*t<2^(m)) with helper (or parity data) to restore the value back where With temperature some bits might change in its value. Furthermore, the authentication engine (160) generates the plurality of parity bits from the generated at least one unique key and detects the error based on the generated plurality of parity bits. At 522, the authentication engine (160). The m*t bits of data ate stored in the OTP for tuning of the image sensor (150).

In an embodiment, the unique key (i.e. PUF key) is exclusive to the electronic device (100). The electronic device (100) does not store the unique key to the memory (110). Hence, the unique key is not available for an external source to hack the unique key.

The proposed method docs not demands any additional hardware for generating the unique key. Hence, the proposed method is a cost-effective technique for the key generation and the authentication.

The proposed method can be used to differentiate a fake CMOS sensors and a genuine CMOS sensors of the electronic device (100).

The proposed method can be used to provide a device-level authentication using the CMOS sensor (150) on the electronic device (100) instead of using IMEI or other passcodes which are stored in the electronic device (100). Furthermore, the proposed method provides watermarking of images captured by the CMOS sensors (150) on the electronic device (100), In case authenticity of the image needs to be established the image can be watermarked with the unique key which can later be used for image authentication.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein. 

What is claimed is:
 1. A method for providing authentication using at least one image sensor of an electronic device, comprises: receiving, by the electronic device, a plurality of frames from the at least one image sensor of the electronic device, wherein each frame includes a plurality of Optical Black (OB) pixels; determining, by the electronic device, at least one set of optimal OB pixel from the plurality of frames; and generating, by the electronic device, at least one unique key based on the at least one set of optimal OB pixel for the authentication.
 2. The method as claimed in claim 1, wherein determining, by the electronic device, the at least one set of optimal OB pixel from the plurality of frames, comprises: determining, by the electronic device, location information of a plurality of OB pixels in a first frame of the plurality of frames, storing, by the electronic device, the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels; determining, by the electronic device, location information of a plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in the remaining frames of the plurality of frames; performing, by the electronic device, an addition between the stored dark current value of the plurality of OB pixels and corresponding the determined dark current value of the plurality of OB pixels of the remaining frames; storing by the electronic device, an average information of the addition; and determining, by the electronic device, the at least one set of optimal OB pixels based on the average information, wherein the at least one set of optimal OB pixels is a higher value set of the stored average information.
 3. The method as claimed in claim 1, wherein determining, by the electronic device, the at least one set of optimal OB pixel from the plurality of frames, comprises: determining, by the electronic device, location information of a plurality of candidate OB pixels in a first frame of the plurality of frames, wherein the plurality of candidate OB pixels obtained from the plurality of OB pixels; storing, by the electronic device, the location information of the plurality of candidate OB pixels; determining, by the electronic device, location information of a plurality of candidate OB pixels in remaining frames of the plurality of frames; performing, by the electronic device, an intersection on the stored location information using the location information of the plurality of candidate OB pixels of the remaining frames; and determining, by the electronic device, the at least one set of optimal OB pixels based on the intersection.
 4. The method as claimed in claim 1, wherein determining, by the electronic device, the at least one set of optimal OB pixel from the plurality of frames, comprises: determining, by the electronic device, location information of a plurality of OB pixels in a first frame of the plurality of frames, storing, by the electronic device, the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels, wherein the stored location information is a higher value set of the first frame; determining, by the electronic device, location information of a plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in remaining frames of the plurality of frames; performing, by the electronic device, an addition between the stored dark current value of the plurality of OB pixels and the determined dark current value of the plurality of OB pixels of the remaining frames and storing addition information; and determining, by the electronic device, the at least one set of optimal OB pixels based on the addition, wherein the at least one set of optimal OB pixels is a higher value set of the stored addition information.
 5. The method as claimed in claim 1, wherein the plurality of OB pixels are present on an active pixel array of the at least one image sensor of the electronic device.
 6. The method as claimed in claim 1, further comprises: generating, by the electronic device, a plurality of parity bits from the generated at least one unique key; and detecting, by the electronic device, an error based on the generated plurality of parity bits.
 7. An electronic device for providing authentication using at least one image sensor, comprising: a memory; processor; and an authentication engine, operably connected to the memory and the processor, configured to: receive a plurality of frames from the at least one image sensor of the electronic device, wherein each frame includes a plurality of Optical Black (OB) pixels; determine at least one set of optimal OB pixel from the plurality of frames; and generate at least one unique key based on the at least one set of optimal OB pixel for the authentication.
 8. The electronic device as claimed in clam 7, wherein determine the at least one set of optimal OB pixel from the plurality of frames, comprises: determine location information of a plurality of OB pixels in a first frame of the plurality of frames, store the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels; determine location information of a plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in the remaining frames of the plurality of frames; perform an addition between the stored dark current value of the plurality of OB pixels and corresponding the determined dark current value of the plurality of OB pixels of the remaining frames; storing an average information of the addition; and determine the at least one set of optimal OB pixels based on the average information, wherein the at least one set of optimal OB pixels is a higher value set of the stored average information.
 9. The electronic device as claimed in claim 7, wherein determine the at least one set of optimal OB pixel from the plurality of frames, comprises: determine location information of a plurality of candidate OB pixels in a first frame of the plurality of frames, wherein the plurality of candidate OB pixels obtained from the plurality of OB pixels; store the location information of the plurality of candidate OB pixels; determine location information of a plurality of candidate OB pixels in remaining frames of the plurality of frames; perform an intersection on the stored location information using the location information of the plurality of candidate OB pixels of the remaining frames; and determine the at least one set of optimal OB pixels based on the intersection.
 10. The electronic device as claimed in claim 7, wherein determine the at least one set of optimal OB pixel from the plurality of frames, comprises: determine location information of a plurality of OB pixels in a first frame of the plurality of frames, store the location information of the plurality of OB pixels and corresponding dark current value of the plurality of OB pixels, wherein the stored location information is a higher value set of the first frame; determine location information of a plurality of OB pixels and corresponding dark current value of the plurality of OB pixels in remaining frames of the plurality of frames; perform an addition between the stored dark current value of the plurality of OB pixels and the determined dark current value of the plurality of OB pixels of the remaining frames and storing addition information; and determine the at least one set of optimal OB pixels based on the addition, wherein the at least one set of optimal OB pixels is a higher value set of the stored addition information.
 11. The electronic device as claimed in claim 7, wherein the plurality of OB pixels are present on an active pixel array of the at least one image sensor of the electronic device.
 12. The electronic device as claimed in claim 7, further comprises: generate a plurality of parity bits from the generated at least one unique key; and detect an error based on the generated plurality of parity bits. 